synthesis of ketone cyanohydrin esters in aqueous media is reported using N-acylbenzotriazoles as the acylating agents. In saturated aqueous sodium bicarbonate containing a catalytic amount of tetrabutylammonium bromide, the reaction of ketones with potassium cyanide and N-acylbenzotriazoles proceeded readily at room temperature to provide the corresponding O-acyl cyanohydrin derivatives in good to excellent
4-(<i>N,N</i>-Dimethylamino)pyridine Hydrochloride as a Recyclable Catalyst for Acylation of Inert Alcohols: Substrate Scope and Reaction Mechanism
作者:Zhihui Liu、Qiaoqiao Ma、Yuxiu Liu、Qingmin Wang
DOI:10.1021/ol4030875
日期:2014.1.3
4-(N,N-Dimethylamino)pyridine hydrochloride (DMAP·HCl), a DMAP salt with the simplest structure, was used as a recyclablecatalyst for the acylation of inert alcohols and phenols under base-free conditions. The reaction mechanism was investigated in detail for the first time; DMAP·HCl and the acylating reagent directly formed N-acyl-4-(N′,N′-dimethylamino)pyridine chloride, which was attacked by the
DBU catalyzed cyanoacylation of ketones with acyl cyanides
作者:Wen Zhang、Min Shi
DOI:10.1039/b602197b
日期:——
The reaction of cyclohexanone with benzoyl cyanide catalyzed by amines provides the corresponding O-benzoyl cyanohydrin adducts in moderate to good yields under mild conditions. Among the catalysts, DBU was found to be the most effective promoter allowing the reaction to proceed smoothly at room temperature and to give the corresponding O-acyl cyanohydrin adducts in higher yields for a variety of substituted cyclohexanones, cyclopentanone, acetone or pentan-3-one and various acyl cyanides.
Reaction of variety of aldehydes and ketones with chlorotrimethylsilane and acyl chlorides in the presence of lithium cyanide to give trimethylsilylcyanohydrins and acylcyanohydrins is described.